A layer of fresh enamel (3)

I believe the answer is:

hen

'a layer' is the definition.
(I've seen this before)

'of fresh enamel' is the wordplay.
'of' indicates the answer is hidden within the clue.
'HEN' is hidden in the letters of 'fresh enamel'.

(Other definitions for hen that I've seen before include "Domestic fowl" , "Clucking female" , "Domestic egg layer" , "Coop resident" , "Source of eggs" .)

I've seen this clue in the Evening Standard.

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